| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.commons.proxy.factory.javassist; |
| |
| import javassist.CannotCompileException; |
| import javassist.ClassPool; |
| import javassist.CtClass; |
| import javassist.CtField; |
| import javassist.LoaderClassPath; |
| import javassist.NotFoundException; |
| import org.apache.commons.proxy.ProxyUtils; |
| import org.apache.commons.proxy.exception.ObjectProviderException; |
| |
| import java.util.HashSet; |
| import java.util.Set; |
| |
| /** |
| * Some utility methods for dealing with Javassist. This class is not part of the public API! |
| * |
| * @author James Carman |
| * @since 1.0 |
| */ |
| class JavassistUtils |
| { |
| //********************************************************************************************************************** |
| // Fields |
| //********************************************************************************************************************** |
| |
| public static final String DEFAULT_BASE_NAME = "JavassistUtilsGenerated"; |
| private static int classNumber = 0; |
| private static final ClassPool classPool = new ClassPool(); |
| |
| private static final Set classLoaders = new HashSet(); |
| |
| //********************************************************************************************************************** |
| // Static Methods |
| //********************************************************************************************************************** |
| |
| static |
| { |
| classPool.appendClassPath(new LoaderClassPath(ClassLoader.getSystemClassLoader())); |
| } |
| |
| /** |
| * Adds a field to a class. |
| * |
| * @param fieldType the field's type |
| * @param fieldName the field name |
| * @param enclosingClass the class receiving the new field |
| * @throws CannotCompileException if a compilation problem occurs |
| */ |
| public static void addField( Class fieldType, String fieldName, CtClass enclosingClass ) |
| throws CannotCompileException |
| { |
| enclosingClass.addField(new CtField(resolve(fieldType), fieldName, enclosingClass)); |
| } |
| |
| /** |
| * Adds interfaces to a {@link CtClass} |
| * |
| * @param ctClass the {@link CtClass} |
| * @param proxyClasses the interfaces |
| */ |
| public static void addInterfaces( CtClass ctClass, Class[] proxyClasses ) |
| { |
| for( int i = 0; i < proxyClasses.length; i++ ) |
| { |
| Class proxyInterface = proxyClasses[i]; |
| ctClass.addInterface(resolve(proxyInterface)); |
| } |
| } |
| |
| /** |
| * Creates a new {@link CtClass} derived from the Java {@link Class} using the default base name. |
| * |
| * @param superclass the superclass |
| * @return the new derived {@link CtClass} |
| */ |
| public static CtClass createClass( Class superclass ) |
| { |
| return createClass(DEFAULT_BASE_NAME, superclass); |
| } |
| |
| /** |
| * Creates a new {@link CtClass} derived from the Java {@link Class} using the supplied base name. |
| * |
| * @param baseName the base name |
| * @param superclass the superclass |
| * @return the new derived {@link CtClass} |
| */ |
| public synchronized static CtClass createClass( String baseName, Class superclass ) |
| { |
| return classPool.makeClass(baseName + "_" + classNumber++, resolve(superclass)); |
| } |
| |
| /** |
| * Finds the {@link CtClass} corresponding to the Java {@link Class} passed in. |
| * |
| * @param clazz the Java {@link Class} |
| * @return the {@link CtClass} |
| */ |
| public static CtClass resolve( Class clazz ) |
| { |
| synchronized( classLoaders ) |
| { |
| try |
| { |
| final ClassLoader loader = clazz.getClassLoader(); |
| if( loader != null && !classLoaders.contains(loader) ) |
| { |
| classLoaders.add(loader); |
| classPool.appendClassPath(new LoaderClassPath(loader)); |
| } |
| return classPool.get(ProxyUtils.getJavaClassName(clazz)); |
| } |
| catch( NotFoundException e ) |
| { |
| throw new ObjectProviderException( |
| "Unable to find class " + clazz.getName() + " in default Javassist class pool.", e); |
| } |
| } |
| } |
| |
| /** |
| * Resolves an array of Java {@link Class}es to an array of their corresponding {@link CtClass}es. |
| * |
| * @param classes the Java {@link Class}es |
| * @return the corresponding {@link CtClass}es |
| */ |
| public static CtClass[] resolve( Class[] classes ) |
| { |
| final CtClass[] ctClasses = new CtClass[classes.length]; |
| for( int i = 0; i < ctClasses.length; ++i ) |
| { |
| ctClasses[i] = resolve(classes[i]); |
| } |
| return ctClasses; |
| } |
| } |
| |